Medial Tibiofemoral Compartment Research Articles

Two Different Knee Rotational Instabilities Occur With Anterior Cruciate Ligament and Anterolateral Ligament Injuries: A Robotic Study on Anterior Cruciate Ligament and Extra-articular Reconstructions in Restoring Rotational Stability

To determine the effect of 2 extra-articular reconstructions on pivot-shift rotational stability and tibial internal rotation as a basis for clinical recommendations. A robotic simulator tested 15 cadaver knees. Group 1 (anterior cruciate ligament [ACL] cut) underwent ACL bone-patellar tendon-bone reconstruction followed by sectioning the anterolateral structures and an extra-articular, manual-tension iliotibial band (ITB) tenodesis. Group 2 (ACL intact) tested the rotational stabilizing effect of a low-tension ITB tenodesis before and after sectioning the anterolateral ligament/ITB structures. Lateral and medial tibiofemoral compartment translations and internal-external tibial rotations were measured under Lachman, 5N·m tibial rotation, and 2 pivot-shift simulations using 4-degree-of-freedom loading. Statistical equivalence was defined within 2mm tibiofemoral compartment translation and 2° tibial rotation at P < .05. The bone-patellar tendon-bone ACL reconstruction (group 1) restored pivot-shift lateral compartment translation within 0.7mm (95% confidence interval [CI], -0.6 to 1.9; P= .70) of normal. The internal rotation limit was not affected by ACL sectioning or reconstruction. After anterolateral ligament/ITB sectioning there was no change in pivot-shift lateral compartment translation, however internal rotation increased 2.9° (95% CI, 0.6-5.2; P= .99) at 90° flexion. The manual-tension ITB tenodesis (fixated 13-22N tension) decreased pivot-shift lateral compartment translation 4.8mm (95% CI, 1.4-8.1; P=.99) and internal rotation by 21.9° (95% CI, 13.2-30.6; P= .99) at 90° flexion. The ACL forces decreased 45.8% in the pivot-shift test. In group 2 knees, with the ACL intact, the anterolateral ligament/ITB sectioning had no effect on pivot-shift translations; however, the internal rotation limit increased by 4.3° (95% CI, 1.9-6.8; P= .99) at 60° flexion. The low-tension ITB tenodesis (fixated 8.9N tension) had no effect on pivot-shift translations and corrected internal tibial rotation with a mild overconstraint of 4.2° (95% CI, 1.9-6.8; P= .99) at 60° flexion. A low-tension ITB tenodesis, fixated at neutral tibial rotation to avoid constraining internal tibial rotation, has no effect in limiting abnormal pivot-shift subluxations. A low-tension ITB tenodesis has limited clinical utilization as the pivot-shift subluxations are not affected, assuming appropriate tensioning to not overconstrain internal tibial rotation.

Knee Kinetics and Kinematics in Patients with Ankle Arthroplasty and Ankle Arthrodesis

Category: Ankle Arthritis Introduction/Purpose: Ankle arthritis is a debilitating problem, causing significant pain and functional limitations. Previous literature suggests patients treated with ankle arthroplasty (TAA) versus ankle arthrodesis (AA) may have better function and have lower risk for adjacent joint arthritis in the foot. However, there is little research on how these interventions impact proximal joints, such as the knee. The knee adduction moment (KAM) is a surrogate measure for the force experienced at the medial tibiofemoral compartment and is linked with the onset and progression of knee osteoarthritis. We hypothesized that patients with TAA and AA will exhibit altered frontal plane kinematics and kinetics in the affected limb compared to the contralateral unaffected side, and that the AA cohort will have a significantly greater KAM compared to TAA. Methods: Instrumented 3D walking gait was recorded in 10 TAA and 10 AA patients, minimum 2-year post-operatively. Subjects were demographically matched, had unilateral ankle arthritis and lacked complications such as adjacent joint arthritis, neuropathy or significant weight-bearing pain. The TAA patients had either a Salto-Talaris or INBONE prosthesis. Lower limb kinematic and kinetic data were measured with reflective skin surface markers and floor-embedded force plates at self-selected walking speeds. Average first and second peak KAMs [N-m/kg], KAM impulse [N-m-s/kg] and range-of-motion (ROM, [°]) were calculated on both the affected and unaffected limb for each patient. Group differences in KAM, impulse and ROM between TAA and AA interventions and the affected and unaffected limb were analyzed using a 2-sample unpaired t test. P-values less than 0.05 were considered significant. Results: See Table 1 for demographic and statistical analyses summary. Between the affected and unaffected limbs in each surgical cohort there were no significant differences in the KAM’s first and second peak or impulse (p&gt;0.135) and no difference in the knee ROM in any plane (p&gt;0.214). When comparing AA with TAA, the average first peak KAMs generated while walking were 0.07N-m/kg greater in the TAA treatment but that difference was not significant (p=0.429). The second peak KAM was, on average, 0.1N-m/kg greater within TAA patients but was also not statistically different from AA patients (p=0.594). The KAM impulse and ROM in all 3 planes were not different between intervention types (p&gt;0.318). Conclusion: TAA and AA may not significantly affect ipsilateral knee kinetics and KAMs in short term follow-up. This study highlights the importance of continuing to study these parameters in larger cohorts of patients with longer follow-up to determine how our treatment of end-stage ankle arthritis may affect the incidence or progression of ipsilateral knee osteoarthritis.

Greater magnitude tibiofemoral contact forces are associated with reduced prevalence of osteochondral pathologies 2-3years following anterior cruciate ligament reconstruction.

External loading of osteoarthritic and healthy knees correlates with current and future osteochondral tissue state. These relationships have not been examined following anterior cruciate ligament reconstruction. We hypothesised greater magnitude tibiofemoral contact forces were related to increased prevalence of osteochondral pathologies, and these relationships were exacerbated by concomitant meniscal injury. This was a cross-sectional study of 100 individuals (29.7 ± 6.5years, 78.1 ± 14.4kg) examined 2-3years following hamstring tendon anterior cruciate ligament reconstruction. Thirty-eight participantshad concurrent meniscal pathology (30.6 ± 6.6years, 83.3 ± 14.3kg), which included treated and untreated meniscal injury, and 62participants (29.8 ± 6.4years, 74.9 ± 13.3kg) were free of meniscal pathology. Magnetic resonance imaging of reconstructed knees wasused to assess prevalence of tibiofemoral osteochondral pathologies (i.e., cartilage defects and bone marrow lesions). A calibrated electromyogram-driven neuromusculoskeletal model was used to predict medial and lateral tibiofemoral compartment contact forces from gait analysisdata. Relationships between contact forces and osteochondral pathology prevalence were assessed using logistic regression models. In patients with reconstructed knees free from meniscal pathology, greater medial contact forces were related to reduced prevalence of medial cartilage defects (odds ratio (OR) = 0.7, Wald χ2(2) = 7.9, 95% confidence interval (CI) = 0.50-95, p = 0.02) and medialbone marrow lesions (OR = 0.8, Wald χ2(2) = 4.2, 95% CI = 0.7-0.99, p = 0.04). No significant relationships were found in lateral compartments. In reconstructed knees with concurrent meniscal pathology, no relationships were found between contact forces and osteochondral pathologies. In patients with reconstructed knees free from meniscal pathology, increased contact forces were associated with fewer cartilage defects and bone marrow lesions in medial, but not, lateral tibiofemoral compartments. No significant relationships were found between contact forces and osteochondral pathologies in reconstructed knees with meniscal pathology for any tibiofemoral compartment. Future studies should focus on determining longitudinal effects of contact forces and changes in osteochondral pathologies. IV.

Mechanical effects of medial and lateral wedged orthoses during running

ObjectiveThe aim of the current investigation was to examine the effects of orthoses with 5° medial and lateral wedges on knee joint kinetics during the stance phase of running. DesignRepeated measures. SettingLaboratory. ParticipantsTwelve recreational runners. Outcome measurementsTwelve male participants ran over a force platform at 4.0 m/s in three different conditions (medial orthotic, lateral orthotic and no-orthotic). Lower limb kinematics were collected using an 8-camera motion capture system allowing knee kinetics to be quantified using a musculoskeletal modelling approach. Differences in knee joint kinetics between orthotic conditions were examined using one-way repeated measures ANOVA. ResultsThe results showed that peak patellofemoral force was significantly increased in the medial (31.81 N/kg) and lateral (31.29 N/kg) wedged orthoses, in comparison to the no-orthotic (29.61 N/kg) condition. In addition, the peak knee adduction moment was significantly increased in the medial (1.10 Nm/kg) orthoses, in comparison to the lateral (0.87 Nm/kg) condition. ConclusionsThe results from this study indicate that lateral orthoses may be effective in attenuating runners risk from medial tibiofemoral compartment OA, but that wedged orthoses may enhance their risk from patellofemoral pain.

Knee extensor muscle weakness and radiographic knee osteoarthritis progression

Background and purpose — Knee extensor (KE) muscle weakness is a modifiable feature commonly observed in individuals with knee osteoarthritis (KOA) and constitutes a potential target for patient-specific interventions. Therefore, in this study, we explored whether KE weakness is associated with radiographic (medial and/or lateral) KOA progression and how this relationship differs depending on frontal plane knee alignment and sex.Patients and methods — We studied 3,075 knees (1,961 participants, 58% female) from the Osteoarthritis Initiative with radiographic Kellgren–Lawrence grade 1–3. Peak KE torque (Nm/kg) was assessed at baseline, and progression defined as fixed-location joint space width loss (≥ 0.7mm) in medial and lateral tibiofemoral compartments from baseline to 4-year follow-up. Knee-based generalized estimating equations, stratified by alignment (malaligned vs. neutral), estimated the relative risk (RR) of progression for those in the lowest (and middle) vs. highest KE torque group (split by tertiles). Secondary analyses explored whether this relationship was compartmental- or sex-specific.Results — Being in the lowest (or middle) compared with the highest torque group increased the risk of progression in neutrally aligned knees (relative risk [RR] 1.2 [95% CI 1.0–1.4]; and 1.2 [CI 1.0–1.4], respectively), but not after adjusting for age, sex, BMI, pain, and radiographic severity. In secondary analyses, women with neutral alignment in the lowest compared with the highest torque group had significantly increased risk of lateral compartment progression independent of age, BMI, disease severity, and pain (RR 1.3 [CI 1.0–1.8]). No association was observed between KE torque and KOA progression in men, irrespective of alignment.Interpretation — These results identify a potentially important clinical phenotype: KE weakness may be a more important risk factor for radiographic KOA progression in women without knee malalignment.

The Effect of Arch Drop on Tibial Rotation and Tibiofemoral Contact Stress in Postpartum Women

BackgroundWomen are at greater risk for knee osteoarthritis and numerous other lower limb musculoskeletal disorders. Arch drop during pregnancy and the resultant excessive pronation of the feet may alter loading patterns and contribute to the greater prevalence of knee osteoarthritis in women. ObjectiveTo determine the effect of arch drop on tibial rotation and tibiofemoral contact stress. DesignInterventional study with internal control. SettingBiomechanics laboratory. ParticipantsEleven postpartum women (age 33.4 ± 5.3 years, body mass 76.1 ± 13.5 kg) who had lost arch height with pregnancy in a previous study. MethodsSubjects underwent standing computed tomography (SCT) with their knees in a 20° fixed-flexed position with and without semirigid arch supports to reconstitute prepregnancy arch height. Magnetic resonance imaging of the knee was acquired at a flexion angle equivalent to that of SCT. Bone and cartilage were manually segmented on the magnetic resonance images and segmented surfaces were registered to the 3-dimensional SCT image sets for the arch-supported and -unsupported conditions. These models were used to measure changes in tibial rotation, as well as to estimate contact stress in the medial and lateral tibiofemoral compartments, using computational methods. Main Outcome MeasuresChange in tibial rotation and tibiofemoral contact stress with arch drop. ResultsArch drop resulted in a mean tibial internal rotation of 0.75 ± 1.33° (P = .02). Changes in mean or peak contact stress were not detected. ConclusionsArch drop causes internal tibial rotation, resulting in a shift in the tibiofemoral articulation. An associated increase in contact stress was not detected. Internal rotation of the tibia increases stress on the anterior cruciate ligament and menisci, potentially explaining the greater prevalence of knee disorders in postpartum women. Level of EvidenceNA

The association between the Mediterranean diet and magnetic resonance parameters for knee osteoarthritis: data from the Osteoarthritis Initiative.

The Mediterranean diet appears to be beneficial for osteoarthritis (OA), but the few data available regarding the association between the diet and the condition are limited to X-ray and clinical findings. The current study aimed to investigate the association between adherence to the Mediterranean diet and knee cartilage morphology, assessed using magnetic resonance (MRI) in a cohort of North American participants. Seven hundred eighty-three participants in the Osteoarthritis Initiative (59.8% females; mean age 62.3years) in possession of a MRI assessment (a coronal 3D FLASH with Water Excitation MR sequence of the right knee) were enrolled in our cross-sectional study. Adherence to the Mediterranean diet was evaluated using a validated Mediterranean diet score (aMED). The strength of the association between aMED and knee MRI parameters was gauged using an adjusted linear regression analysis, expressed as standardized betas with 95% confidence intervals (CIs). Using an adjusted linear regression analysis, each increase of one standard deviation (SD) in the aMED corresponded to a significant increase in the central medial femoral cartilage volume (beta = 0.12; 95%CI 0.09 to 0.15), in the mean central medial femoral cartilage thickness (beta = 0.13; 95%CI 0.01 to 0.17), in the cartilage thickness of the mean central medial tibiofemoral compartment (beta = 0.12; 95%CI 0.09 to 0.15), and in the cartilage volume of the medial tibiofemoral compartment (beta = 0.09; 95%CI 0.06 to 0.12). Higher adherence to a Mediterranean diet was found to be associated with a significant improvement in knee cartilage as assessed by MRI, even after adjusting for potential confounding factors.

A novel method for assessing proximal tibiofibular joint on magnetic resonance images in patients with knee osteoarthritis

Purpose: Knee osteoarthritis (OA) is well accepted as a whole organ disease that involves abnormalities of various structures. Proximal tibiofibular joint (ProxTibFibJ) is a synovial sliding joint that has been estimated to transmit one-sixth of the leg’s static load. Despite extensive studies on tibiofemoral and patellofemoral compartments, little attention has been paid to the ProxTibFibJ in OA research. One study has reported that proximal fibular osteotomy could significantly improve the clinical outcomes in patients with medial compartment OA. However, no study has delineated the measurement of ProxTibFibJ morphological parameters (ProxTibFibJ contacting area, load-bearing area, lateral stress-bolstering area and posterior stress-bolstering area) on magnetic resonance imaging (MRI) and investigated their correlations with knee OA structural abnormalities. This study, therefore, is to describe and validate a pragmatic method of measuring the ProxTibFibJ morphological parameters, and to investigate the longitudinal associations with joint abnormal structural changes in patients with knee OA. Methods: A total of 408 participants with knee OA were selected from the Vitamin D Effects on Osteoarthritis (VIDEO) Study, which was a multi-center, randomized and double-blind clinical trial. ProxTibFibJ morphological parameters were measured on coronal and sagittal MRI. The contacting area of ProxTibFibJ (S), its projection areas onto the horizontal (load-bearing area, Sτ), sagittal (lateral stress-bolstering area, Sφ) and coronal plane (posterior stress-bolstering area, Sυ) were assessed, respectively. MRI knee structural abnormalities, including cartilage defects, bone marrow lesions (BMLs) and cartilage volume, were evaluated at baseline and 2 years later. Ordinal logistic regression analyses were used to assess the cross-sectional associations between ProxTibFibJ morphological parameters and cartilage defects, BMLs, osteophytes, and JSN. Log binominal regression and linear regression models were used to assess the longitudinal associations between ProxTibFibJ morphological parameters and osteoarthritic structural changes. The reliabilities were examined by calculating the intra- and inter-observer correlation coefficients. Results: The average ProxTibFibJ fibular contacting area was 2.4 ± 0.7 cm2. The intra- and inter-observer correlation coefficients for all measures were excellent (all ≥0.90). In cross-sectional analyses, the ProxTibFibJ morphological parameters (S, Sτ, Sυ and Sφ) were significantly associated with radiographic medial JSN (OR 1.72 for S; 2.20 for Sτ; 1.65 for Sυ), radiographic medial osteophyte (OR 0.51 for Sφ) and MRI-assessed knee joint structural abnormalities including cartilage volume (β −0.07 for S; −0.09 for Sτ), cartilage defects (OR 1.63 for S; 1.95 for Sτ) and BMLs (OR 1.54 for S; 1.74 for Sτ) at medial tibiofemoral compartment. In longitudinal analyses, S (RR, 1.45) and Sτ (RR, 1.55) of ProxTibFibJ were significantly and positively associated with an increase in medial tibial cartilage defects over 2 years, after adjustment for age, gender, height, weight, ROA, tibial plateau bone area and intervention. Sτ (β, −0.07), Sυ (β, −0.07) and S (β, −0.06) of ProxTibFibJ were significantly and negatively associated with change in medial tibial cartilage volume, after adjusted for above covariates. Sτ (RR, 1.55) of ProxTibFibJ was positively associated with an increase in medial tibial BML, and Sφ (RR, 0.35) was negatively associated with an increase in medial femoral BMLs. No significant associations were found between ProxTibFibJ morphological parameters and osteoarthritic changes in lateral tibiofemoral compartment. Conclusions: This novel method to assess the morphological parameters of ProxTibFibJ using MRI is reproducible, and has clinical construct validity. The longitudinal associations with osteoarthritic changes suggest that higher load-bearing area of ProxTibFibJ is a potential risk factor for medial compartment OA. This may contribute to a theoretical basis of proximal fibular osteotomy in the treatment of medial tibiofemoral OA.

Defining the factors that alter OA risk following ACL injury using pre-clinical animal models

Purpose: Osteoarthritis (OA) is a common long-term outcome of anterior cruciate ligament (ACL) injuries, but still only ∼50% of ACL deficient knees develop OA. Concomitant meniscal or chondral damage substantially increases OA risk, however factors affecting OA development in isolated ACL tears are less defined. There is evidence to suggest that the impact at the time of ACL injury may be an important risk factor in addition to altered joint mechanics. The aim of this study was to investigate changes in joint mechanics, pain behaviours and OA pathogenesis in models of isolated ACL injury comparing minimal impact trauma (surgical transection) with compression induced ligament failure (mechanical rupture). Methods: Ten-week-old, male C57BL/6 mice were randomised into 4 groups: 1) uninjured, 2) sham surgery, 3) surgical ACL transection (ACLT), or 4) mechanical ACL rupture (mACLR). Outcomes were measured at 1, 2, 4 and 8 weeks post-injury. Ex vivo knee mechanics (range of motion and joint stiffness) were measured using an anterior-posterior (AP) laxity tester (n = 6/group). Pain behaviour was assessed using von Frey filaments (mechanical allodynia) or an incapacitance tester (static weight-bearing) and included pre-injury tests (n = 6/group). OA severity in the medial and lateral tibiofemoral compartments was scored histologically for: proteoglycan loss, cartilage structural damage, osteophyte development, subchondral bone sclerosis and synovitis (n = 7/group). Results: ACL injury significantly altered the mechanics of the knee whilst sham surgery did not differ from uninjured joints. AP range of motion increased equally (3-fold) following ACLT and mACLR (P < 0.02), with no improvement up to 8 weeks post-injury. Anterior joint stiffness increased over time in controls. ACLT stiffness was significantly lower than sham at 1 and 2 weeks post-injury (P < 0.02) with some recovery at 4 weeks, whilst mACLR remained largely unchanged but significantly less than uninjured at 4 and 8 weeks post-injury (P < 0.01). Significant mechanical allodynia was equally evident at all time points following sham surgery, ACLT and mACLR (P < 0.001 vs pre-injury). In contrast, weight-bearing was only reduced in ACL injured limbs (1–8 weeks post-injury, P < 0.01 vs pre-injury both ACLT and mACLR). OA pathology was found in both the medial and lateral compartments, but was substantially worse in the former. Differences between the two ACL injury models were also more evident medially. The development and progression of medial cartilage pathology was slower following ACLT compared to mACLR: proteoglycan loss and cartilage damage were not significantly increased until 8 weeks post-ACLT (P < 0.005) whilst mACLR induced significant changes by week 2 (P < 0.001). Similarly, significant osteophyte formation was not evident until 8 weeks post-ACLT (P < 0.005) but was present 1 week after mACLR (P < 0.005). Subchondral bone sclerosis was elevated following mACLR but was not significantly different from ACLT or controls. Synovitis was greatest following ACLT at 1 week post-injury (P < 0.005) but was no different between ACLT, mACLR and sham surgery from 2–4 weeks. At 8 weeks, sham surgery synovitis had returned to uninjured levels whilst ACLT and mACLR remained slightly elevated (P < 0.005). Conclusions: These results show that loss of ACL integrity, irrespective of the mechanism of injury, causes severely altered joint mechanics and increased pain responses. Despite these functional and symptomatic similarities, pathological progression of disease was vastly different between the two models. ACL transection results in a slowly progressive OA whilst compressive rupture induces rapid onset and progression. These findings indicate that pain and anterior–posterior joint mechanics are not predictive of OA severity but the acute trauma itself can significantly influence the outcome of disease. Defining ways to determine compressive loading experienced at the time of ACL injury, could improve prediction of OA risk and patient management.

Compartmental distribution of osteoarthritic features amongst people with chronic knee pain: a magnetic resonance imaging study

Purpose: To explore the prevalence of osteoarthritic features identified on magnetic resonance imaging (MRI), in the compartments of the knee amongst people with chronic knee pain. Methods: 304 MRI scans from people aged 45 to 75 years with chronic knee pain participating in a randomised clinical trial evaluating dietary supplements were assessed. The MRIs were evaluated by the primary investigator (SK) using the MRI Osteoarthritis Knee Score (MOAKS). Bone marrow lesions (BML) size, cartilage loss and osteophytes were assessed on sagittal, axial and coronal plane scans. The knee was divided into the patellofemoral (PF), medial tibiofemoral (TF) and lateral TF compartments. Weighted kappa was used to assess intra-rater reliability. Frequency and vend diagrams were used to assess prevalence patterns of OA features in the compartments. Results: For all severities of BML size and full thickness cartilage loss, isolated PF involvement was the most common pattern (BML: 7.9–15.1%; cartilage loss: (13.2–20.7%). Tricompartmental patterns (14.8–22.4%) were the most common for osteophytes, followed by combined PF joint and medial TF joint involvement (13.8%) for mild osteophytes. Conclusions: Amongst a cohort of people with chronic knee pain, there was more involvement in the PF joint than the TF joint. Management strategies for knee OA should target risk factors for the PF joint.

Association of mucoid degeneration of the anterior cruciate ligament at MR imaging with medial tibiofemoral osteoarthritis progression at radiography data from the osteoarthritis initiative

Anterior cruciate ligament mucoid degeneration at MR imaging in participants with or at risk for osteoarthritis is associated with progression of medial tibiofemoral compartment joint space loss at radiography, especially in knees with less baseline cartilage surface area damage.

Effect of Neuromuscular Training with Rigid Tape Versus Strength Training on Functional Performance of Knee Osteoarthritis

AbstractBackground: Osteoarthritis of the knee involving predom-inantly the medial tibiofemoral compartment is common in older people, giving rise to pain and loss of function, Neu-romuscular exercises are typically performed in functional weight-bearing positions emphasizing quality and efficiency of movement, as well as Rigid taping (RT) is an effi-cient way of treatment of pain relief.Purpose: This study was conducted to detect the effect of neuromuscular training with Rigid taping versus strength training on functional mobility in medial compartment knee osteoarthritis.Methods: This study was conducted on thirty patients both gender with mild to moderate OA of medial compartment knee OA . Their age ranged from 45-55 years old. All patients were referred by orthopedic surgeons who are responsible for diagnosis based on clinical and radiological examination. They were randomly assigned into two groups Group (A) received strength training exercises and Group (B) received neuromuscular exercises with rigid tape for three sessions per week for one month. The study was conducted from September 2016 to May 2017 at the department of physical therapy at Abo Keir Hospital, Alexandria, at the out clinic at pharous university and a Private hospital at Alexandria.Methods of Evaluation: Thirty seconds chair stand test (30-CST) test for the assessment of functional performance,Results: Showed that both strength training (group A) and neuromuscular exercises with rigid tape (group B) were effective in improvement of functional performance, but strength training (Group A) were less effective than neuromus-cular exercises with rigid tape.Conclusion: It can be concluded that both strength training and neuromuscular exercises with rigid tape are effective treatment for medial compartment knee OA in terms of func-tional performance.

The Clinical Significance of Osteophytes in Compartments of the Knee Joint With Normal Articular Cartilage.

The purpose of this study is to determine whether marginal osteophytes in compartments with normal cartilage would be more frequently observed in knees with cartilage lesions and osteophytes in other compartments. This retrospective study reviewed 500 consecutive knee MRI examinations performed within 6 months of arthroscopic knee surgery conducted for 497 patients with symptoms (289 male patients and 208 female patients; age range, 17-74 years; median age, 43 years). The highest grade of cartilage lesion detected at MRI and arthroscopy was recorded. Marginal osteophytes were graded on MRI with use of a standardized scoring system, with grade 0 denoting no osteophyte; grade 1, small osteophyte; grade 2, medium-size osteophyte; and grade 3, large osteophyte). The frequency of false-positive osteophytes, defined as osteophytes present in compartments (the patellofemoral, medial tibiofemoral, and lateral tibiofemoral compartments) with normal cartilage observed on MRI and arthroscopy, was calculated. The Goodman and Kruskal gamma statistic was used to test the association of osteophyte size between compartments. Logistic regression was used to test the association between osteophyte size and the severity of the cartilage lesions. Marginal osteophytes were seen in compartments with normal cartilage on MRI and arthroscopy in 60.5% of knees (75 of 124) with cartilage lesions and osteophytes in other compartments and accounted for all false-positive grade 2 and grade 3 osteophytes. Marginal osteophytes were seen in 12.7% of knees (13 of 102) that had no cartilage lesions in any compartment on MRI or arthroscopy, and all of these were grade 1 osteophytes. The presence of larger sized osteophytes in the compartments with cartilage lesions was associated with the presence of larger sized osteophytes in the compartments with normal cartilage. More severe cartilage lesions were associated with larger osteophyte size. Compartments with marginal osteophytes and normal cartilage are commonly seen in knees that have other compartments with osteophytes and cartilage lesions.

Association of Mucoid Degeneration of the Anterior Cruciate Ligament at MR Imaging with Medial Tibiofemoral Osteoarthritis Progression at Radiography: Data from the Osteoarthritis Initiative.

Purpose To determine whether anterior cruciate ligament (ACL) mucoid degeneration in participants with or at risk for osteoarthritis is associated with longitudinal risk of radiographic progression of medial tibiofemoral compartment joint space loss (JSL). Materials and Methods Baseline demographic, clinical, radiographic, and Magnetic Resonance (MR) Imaging Osteoarthritis Knee Score (MOAKS) data were evaluated in 600 participants from the Osteoarthritis Initiative database. Two blinded musculoskeletal radiologists independently evaluated baseline MR images for ACL mucoid degeneration. Multiple logistic regression was used to investigate the association between ACL mucoid degeneration at MR imaging and JSL progression at radiography, defined as a minimum joint space width decrease greater than 0.7 mm (48 months; cutoff according to mean and standard deviation of 1-year minimum joint space width changes in 90 knees of reference group). Stratified analysis was performed based on baseline cartilage surface damage. Results Knees with ACL mucoid degeneration showed a greater proportion of JSL progression compared with knees with a normal ACL (64% vs 47%; P = .004). After adjustment for all demographic, clinical, radiographic, and MOAKS variables, ACL mucoid degeneration was not statistically significantly associated with JSL progression in the entire cohort (adjusted odds ratio, 1.66; 95% confidence interval: 1.00, 2.77; P = .051). In subgroup analysis, ACL mucoid degeneration was statistically significantly associated with JSL progression in participants with less baseline cartilage surface damage (maximum cartilage surface loss of ≤75% in all subregions [P = .015] and ≤4 of involved subregions with cartilage surface loss [P = .028]). Conclusion ACL mucoid degeneration in participants with or at risk for osteoarthritis is associated with progression of medial tibiofemoral compartment JSL in knees with less baseline cartilage surface area damage. © RSNA, 2018 Online supplemental material is available for this article.

Medial meniscus grafting restores normal tibiofemoral contact pressures.

Tissue excision in the setting of a meniscal tear has been shown to dramatically increase peak contact stresses in the affected tibiofemoral joint compartment, leading to the development of degenerative changes and osteoarthritis. The current in vitro study utilized a porcine model to evaluate the effectiveness of segmental medial meniscal grafting following partial meniscectomy. The study hypothesis was that the procedure would normalize medial tibofemoral joint compartment pressure magnitudes, areas, and locations relative to an intact meniscus. Controlled laboratory study. Using pressure film, medial tibiofemoral joint compartment peak, and mean pressure magnitudes, peak pressure location and peak pressure area were determined using 12 potted, fresh frozen, porcine knee specimens. Data were collected at three different knee flexion angles (90°, 45°, and 0°) for three conditions: intact medial meniscus, following resection of the central third of the medial meniscus, and following segmental medial meniscal grafting. For each condition, the potted femur was positioned horizontally in a bench vise clamp, while a 20 pound (88.96N) axial compression force was manually applied for a 60s duration by the primary investigator through the base of the potted tibia using a digital force gauge. Loss of the central 1/3 of the medial meniscus resulted in significant increases in the mean and peak pressures of the medial tibiofemoral joint compartment and decreased peak pressure area. Segmental meniscal grafting of the central third defect closely recreated the contact pressures and loading areas of the native, intact medial meniscus. From a static, time zero biomechanical perspective, segmental medial meniscus grafting of a partially meniscectomized knee restored mean pressure, peak pressure, and mean peak contact pressure areas of the medial tibiofemoral joint compartment back to levels observed in the intact medial meniscus at different knee flexion angles. In-vivo analysis under dynamic conditions is necessary to verify the healing efficacy and ability of the healed segmental medial meniscal allograft to provide long-term knee joint homeostasis when confronted with dynamic shear, rotatory, and combined, higher magnitude physiologic loading forces.

The ideal posture in power position related to the spinal alignment

The aim of the current investigation was to examine the effects of orthoses with 5° medial and lateral wedges on knee joint kinetics during the stance phase of running.Repeated measures.Laboratory.Twelve recreational runners.Twelve male participants ran over a force platform at 4.0 m/s in three different conditions (medial orthotic, lateral orthotic and no-orthotic). Lower limb kinematics were collected using an 8-camera motion capture system allowing knee kinetics to be quantified using a musculoskeletal modelling approach. Differences in knee joint kinetics between orthotic conditions were examined using one-way repeated measures ANOVA.The results showed that peak patellofemoral force was significantly increased in the medial (31.81 N/kg) and lateral (31.29 N/kg) wedged orthoses, in comparison to the no-orthotic (29.61 N/kg) condition. In addition, the peak knee adduction moment was significantly increased in the medial (1.10 Nm/kg) orthoses, in comparison to the lateral (0.87 Nm/kg) condition.The results from this study indicate that lateral orthoses may be effective in attenuating runners risk from medial tibiofemoral compartment OA, but that wedged orthoses may enhance their risk from patellofemoral pain.

The influence of hamstrings dynamic stretching on acute performance and distance in young male elite golfers: A Randomized clinical trial

The aim of the current investigation was to examine the effects of orthoses with 5° medial and lateral wedges on knee joint kinetics during the stance phase of running.Repeated measures.Laboratory.Twelve recreational runners.Twelve male participants ran over a force platform at 4.0 m/s in three different conditions (medial orthotic, lateral orthotic and no-orthotic). Lower limb kinematics were collected using an 8-camera motion capture system allowing knee kinetics to be quantified using a musculoskeletal modelling approach. Differences in knee joint kinetics between orthotic conditions were examined using one-way repeated measures ANOVA.The results showed that peak patellofemoral force was significantly increased in the medial (31.81 N/kg) and lateral (31.29 N/kg) wedged orthoses, in comparison to the no-orthotic (29.61 N/kg) condition. In addition, the peak knee adduction moment was significantly increased in the medial (1.10 Nm/kg) orthoses, in comparison to the lateral (0.87 Nm/kg) condition.The results from this study indicate that lateral orthoses may be effective in attenuating runners risk from medial tibiofemoral compartment OA, but that wedged orthoses may enhance their risk from patellofemoral pain.

Application of pie-crusting the medial collateral ligament release in arthroscopic surgery for posterior horn of medial meniscus in knee joint

To explore the effectiveness and safety of pie-crusting the medial collateral ligament release (MCL) in treating posterior horn of medial meniscus (PHMM) tear in tight medial tibiofemoral compartment of knee joint. Methods: Thirty-two consecutive patients with PHMM tear in tight medial tibiofemoral compartment of knee joint were admitted to our department from January, 2013 to December, 2014. All patients were performed pie-crusting the MCL release at its tibial insertion with 18-gauge intravenous needle. All patients were evaluated by valgus stress test and bilateral valgus stress radiograph at postoperative 1st day, 4th week and 12th week. Visual Analogue Scales (VAS), Lysholm scores, Tegner scores and International Knee Documentation Committee (IKDC) scores were recorded at the 1st, 3th, 6th month follow-up, then follow-up every 6 months. Results: The mean follow-up was 28 (24-36) months. All cases were negative in valgus stress test. MCL rupture, femoral fracture, articular cartilage lesion and neurovascular injury were not found at the last follow-up. The median medial joint space width of affected side and unaffected side for valgus stress radiographs were 6.8 mm and 4.3 mm (P<0.05) at the 1st day, 5.5 mm and 4.2 mm (P<0.05) in the 4th week and 4.8 mm and 4.3 mm (P>0.05) at the 12th week, respectively. VAS scores was changed from 4.5±1.5 preoperatively to 1.7±1.0 at the final follow-up (t=16.561, P<0.05). Lysholm scores was changed from 52.3±5.8 preoperatively to 93.2±6.3 at the final follow-up (t=-41.353, P<0.05). Tegner scores was changed from 4.1±1.1 preoperatively to 5.5±0.6 at the final follow-up (t=-18.792, P<0.05). IKDC scores was changed from 54.5±6.2 preoperative to 93.8±4.5 at the final follow-up (t=-38.253, P<0.05). Conclusion: Pie-crusting the medial collateral ligament release is a safe, minimal invasive and effective surgical option for posterior horn of medial meniscus tear in tight medial tibiofemoral compartment of knee joint.

Combined intra- and extra-articular grafting for revision ACL reconstruction: A multicentre study by the French Arthroscopy Society (SFA)

BackgroundA careful analysis of the reasons for ACL reconstruction failure is essential to selection of the optimal surgical revision technique designed to ensure good rotational stability and to minimise the risk of re-rupture. ObjectiveTo evaluate anterolateral ligament (ALL) stabilisation during revision ACL reconstruction. HypothesisALL stabilisation during revision ACL reconstruction provides good rotational stability without increasing the risk of complications. Material and methodsThis multicentre study included 349 patients, 151 retrospectively and 198 prospectively. There were 283 males and 66 females. Inclusion criteria were an indication for revision ACL reconstruction surgery with combined intra-articular reconstruction and ALL stabilisation after failed autograft ACL reconstruction, and intact PCL. Exclusion criteria were primary ACL reconstruction and concomitant peripheral medial and/or lateral lesions. Each patient underwent a clinical and radiographic evaluation before and after revision surgery. Before revision surgery, the mean IKDC score was 56.5±15.5 and 96% of patients were IKDC C or D. ResultsRates were 5.0% for early and 10.5% for late postoperative complications. Lachmann's test had a hard stop at last follow-up in 97% of patients. The pivot-shift test was positive in 1% of patients. The mean subjective IKDC score was 84.5±13.0 and 86.5% of patients were IKDC A or B. The proportions of patients with radiographic knee osteoarthritis at last follow-up was unchanged for the lateral tibio-femoral and patello-femoral compartments but increased by 9.7% to 21.2% for the medial tibio-femoral compartment. The re-rupture rate was 1.2% and the further surgical revision rate was 5.4%. ConclusionAnterior laxity at last follow-up was consistent with previous studies of revision ACL reconstruction. However, rotational stability and the re-rupture risk were improved. ALL stabilisation is among the techniques that deserve consideration as part of the therapeutic options for revision ACL reconstruction. Level of evidenceIV, retrospective and prospective cohort study.

Terminal Condylar Facets of the Femur: Implications for Knee Arthroplasty.

In wake of changing lifestyle and increasing surgical expertise, knee replacement surgeries have become common. Attempts at improving the postoperative range of motion have prompted high-flexion knee arthroplasties. Consequently, there is a need to study the anatomy of knee joint in high flexion. This study focused on a holistic description of terminal condylar articular facet (TCAF; part of the femoral articular area in contact with the tibia in high flexion) of medial and lateral condyles and their quantification. In total, 104 dry femora and 16 dissected cadaveric knee joints (10 adult and 6 fetal) were studied. In most cases, the medial TCAF showed a tongue- or wedge-shaped extension in its lateral half, which has been referred to as extended condylar facet (ECF). The surface area of the ECF was approximately 0.5 cm2. In adult cadaveric dissections, the fibrous capsule showed the lax attachment beyond the ECF, thus creating a cave in the medial tibiofemoral compartment. These features were absent in fetal dissection. The presence of an ECF has not been documented in dry bones and has not been quantified. The variability of the size of this extension supports the hypothesis of this being an acquired trait. This study is expected to provide factual data for implant design improvement and a new anthropological data on Indian femora.